Automatic train-control system



Sept. 7 1926.

Filed August 7 1925 l atented Sept.

; owner-.4 v", Jf lfi ml,- a EDWARD C. SASNETT, 0F \VASHINGTON, DISTRICT OF COLUMiIA. I

Aurortit'rio tenements system;

Appnctian med Aitgiisi 7, issl serial No; 49,748;

The present invention rla'te's to automatic train control systems or the continuous iridication type.

One of the objects of the inventionis to provide a continuous indication system 111 which the various indications'are made dependent uponth'e; reception of electrical iinpulses of aspredet er inined' character; .An: other, object is to provide asysten'i of this type in which thesignalling-energy istransniitt'e'd to" the ve'hi'cle's througli a third' rail or power conductor. Other objects and advantages of the system will become apparent hereinafter. t

Asill'u'strated, the system is applied to a stretch of railroad on which vehicles are electrically propellediby continuous current, but it willjbe understoodtthat the'systeinis equally applicable to roads using alternating current.

i Fig. 1 of the accompanying drawings is'a diagrammatic View showing a system emoo'clying the invention. r

A's customary in the signalling of" roads using continuous propulsion current, the track is divided ,by insulated joints into blocks, with adjoininghlocks connected- 'byinductive bonds, which provide a, free passage for power current flowing through the rails in parallel but prevent the passage-of signalling current flowing throughthe rails in series, P designates the power rail divided by insulated joints into sections c'oinoident with-the blockirsections and provided with inductive bonds bridging the joints, whereby the rail is rendered conductive with respect to the continuous propulsion ClllIBl'll'g but is divided into insulated sections with respect to the alternating signaling current.

' Each block is provided with a relay .10 connected across the rails at the entrance ends of the blocks and with a source of a1- ternatin'g signalling; current connectedat the exit ends, such sourcesg lin' the present in;

*- stance, being portionsof the secondaries; of

7 transformers T, the primaries of thesetransformers being connected across a-pair of alternat ngg current power mains.

-Each block stationils equipped with a gle v hase motor 200; geared to a canrdisk 201. At station A the cam disk 201 has a raised portion extending throughan are of substantially 90" at station B the raised portion extends through an arc 0f1 80 at; station the raised, portion extended through anarcof 90 l hat the raised 1 portions extend through arcs of 90 and I 180 respectively atalternatstations If it beassunied that the camdisks 201 make one revolution every. four seconds, controller 202 at station. A- willconnect the secondary of transformer T across thethirdrailand track front contacts of relay 10coi1necte'dtoblobk A, for asperi'od of onys'ecoiid and disconnect it for'thi'ee seconds every four; seconds At stationiB the controller 202will connect the secondary of the transformer across the" track and third rail fora period 'c'v'ftt'woi,v seconds and disconnect it for a period of twotseconds every :four seconds, etc;

On the vehicle there;is'aconstaiit: sp'ee carryingatits free end a, brush QOSada-pted to, {bridge stationary contacts V209: and 21-05; hen the clutchlis deenergizedfthe arnnis held byfa spring 211 or against astjop 212.

Aj shaft 2l6 ismounted in shaft 204 and adapted to' be clutched ;there"- equivalent HiQtlIlS to -by an electromagnetic ,clutch-217. An

arm 218 is fixed onshaft'216 an isjheld-by aspringQQQ, against a stop 219 whenithe clutch is deenergized The arnn ;c'arifies a brush 221 adapted to bridge stationary ,c'onmots-222 and 223; i Thecircuits of stick 15 lays 22 i and 22 5; are. controlled by]tl1e j con;[ I

tacts 209 2 10 and 222; 223, as wilhheipresy p te o U d r th jo QQ t fQl of the stick relays is a relay 226; which vin turn controls any'suitable tl'aing governing mech mZ MI I, a cl ar ign lamp 2 -5 3 The vehicle equ1p1nent also includes a;. ;so

l oi av ng s p unger co ec d a da :pot 1 ith pr m setpjir er the d wn r m em n f han less-r b urs:- i era qui kri up th of!jThej0 n0 s a pt d f0 xi t rm t tly cner izedi e w l pp a 11 101 2; as i i e fe zat t-- p ed e mine i lsi p n i wo, pa rspt contacts231 and'232:are bri-dged. -A re lay lilticer t ainiconditions, as will hereafter be d j 1 .Wfiththe vehicle in the block to the left of ductors 241,. 242 and 243.

A, and the latter clear, it will be understood from the foregoing that the relay 40 will be energized for onesecond and deencrgized for three seconds, every four seconds. The raised portion of cam 201 has just closed the controller 202 an'd'the relay 40 isv accoroingly shown energized. The circuit of clutch 206 is closed from battery B through the front contact spring of relay 40 and the arm 207 is just beginning its upward rocation. At the end of the one second period brush 208has bridged contacts 209. VVhe-n relay 40 drops, the following circult is closed slightly in advance of the opening of. the circuit of clutch 206: battery B, conductor 234, back contact spring 235, conductor 236, contacts 209,"conductor 237, conductor 238, stick relay 225., solenoid 229 and back to battery-through conductors239 and 240. The circuit of clutch .217 is also closed at back contact spring 235 through con- An impulse, is thus sent through stick relay 225 and sole noid 229 and shaft 216 is clutched to motor shaft204. At the end of the three second interval in which relay 40 is deenergize'd brush 221 has bridged contacts 223, and when relay 40 picks up the following circuit will be closed slightly in advance of the deenergization of clutch 217 battery B, conductor 234, from contact spring 244, conductor 245, contacts 223, conductors 246 and 238, relay 225, solenoid 229 and conductors 239-and 240 back to battery. Thus, as before, an impulse is sent through relay 225 and solenoid 229. It will be understood therefore that as long as the Vehicle is in the block to the left of A, under clear conditions, impulses will be sent through relay 225 and solenoid 229, two every four seconds,

there being a maximum interval of three seconds between impulses.

lvVhen thevehicle passes into block A, with block B clear, it willreceive signalling ener- I i gy during the time controller 202 at station 'twoseconds. During the two second period in which relay 40 is energized arm 207 will move into a position where brush 208 bridges contacts 210; and when the-relay is deenergized the following circuit will be mo mentarily closed: battery B, conductor 234, back contact spring, 235, conductor236, contacts 210, conductors 247 and 248, relay 224, solenoid 229 and conductors 239 and 240 back to battery. At "the endmof the two second interval in which relay 40 is deenergized,

brush 221 on arm 218 has bridged contacts 222 and when the relay picks up, the following circuit will be momentarily'closed:

battery B, conductor 234, front contact,

spring244,conductor 245, contacts 222, cone ductors 249 and 248, relay 224 and solenoid 229, and conductors 239 and 240 to battery. Thus before a momentary impulse is sent through stick relay 224 and solenoid 229 Thus as long as the vehicle is in block A,

with block B clear,"i1npulses will be sent through stick relay 224 and solenoid 229,

one every two seconds.

When relay.225 is picked up it is held by the following stick circuit: battery 15, conductors 240 and 250, contacts 232, conductor- 251, front contact 252, conductor 253,

ductors 255 and 256, contacts 231, and back to batterythrough conductor 257. lVhen relay 224 is picked up it is held by the following stick circuit: battery B, conductors 240 and 250, contactsv 232, conductors 251 and 258, front contact 259, the winding of relay 224, conductor 260, front contact 261,

"conductors 262 and 256, contacts 231, and

The actionof the dash pot 230 is made such that the stick circuits are not opened unless the interval separating impulses is. in 8X- cess of five seconds.

When both stick relays are energized a I train control circuit is closed as follows: batthe winding of relay 225, front contact 254, con.

tery B, conductors 240. and 239, conductor 263,"relay 226, front contacts of relays 225 and 224 in series, and back to battery through conductor 264. Relay 226 when energized closes the circuits of suitable train control mechanism 227 and a green lamp 228. hen the vehicle enters a block directly in rear of an occupied block, it willno longerreceive impulses,'and accordingly at the end of'threeto five seconds from such entry the stick circuits of relays 224 and 225 will be opened, and these relays will clroppopening thecircuit of relay 226, which-in turn will open the circuits of train control mechanism 227 and green lamp 228 It is to be under as the time for a complete cycle of operations merely by way of example. This period may be varied as desired.

When a vehicle has once entered a block to the rear of an occupied block, and relays 224 and 225 have dropped, the train control devices cannot be cleared until 7 the block in advance has been clearedand the vehicle enters this block at a'time whenthe block in advance thereofis clear. -That is,v it is necessary that both stick relays 224 and be encrgized in orderto clear the train control devices, and this cannot occur until relay 40 has been 'operated'by current intwo' adjacent blocks. "Magnet 223 is provided to indicate, after the vehicle has entered" ablock to the rearof an occupied block, When;-

stood that the period of four seconds is given 7 r the latter is cleared. It will be observed that this magnet is intermittently energized uponreceptionof impulses fromany block and will therefore flash the lamp 228 when under the vconditions stated the. block in ad? vance is clear.

Various changes may be made in the sys-.

I tems described and other substantially ditferent mcfdificationsmay bev employed with outdeparting from the scope of the inven' tion as defined in'the claims. a

' I claim: I 1. In an automatic train control system, a

track and a, conductor parallel thereto, -di-' vided by, insulated joints into blocks, a

closed track circuit for each block including a relay, means controlled by. the track relays-for connecting between the track and conductor currents of different characteristics in the case of different blocks, a vehicle on the track having 'a translating device con nected across the conductor. andtrack, selec tivemechanism controlled by the translating device, train control devices, and means governed by the selective mechanism for,

clearing said train control devices when said translatmgdevicehas been successively operated by currents of aplurality of said characteristics. 1 D I 2. In an automatic tralncontrol system, a track and a conductor par'a'llel'thereto, di-

vided by insulatedv joints into blocks, .a

closed track circuittoreach block including a relay, means controlled by the track relays "for connecting between the track and .co-n-i duetor of each block signalling currents having 'diiierent characteristics in the case of adjacent blocks and the same characteristics in the case of alternate blocks,*a vehicleon the track having a translating device connected across the conductor and track, selective mechanism controlled by the translating device, train control devices, and 'means governedby-the selective mechanism for clearing said train control devices when the translating device has been successively operated by currents of diiferent characteristics. v Y I 3. In an automatic train control system,

a track and a conductor parallel thereto, di-

vided by insulated joints into blocks, a closed track circuit for eachblock including a relay, means controlledby the'track relays i for connecting between the track and con-, ductor of each block signalling currents having different characteristics in the case of adjacent blocks and the same cha'racteristics in the case of alternate blocks, a vehicle on the track having atranslating device c0nnected across the conductor and track, twol stlck relays, selective mech-anlsm controlled by the translating device-adapted'to close the pick-up circuit-through one or the other, relay upon reception of current of one or lithe other characteristic,slow acting means for closing the stick 'circui-ts of the relays upon reception of current of eitherjcharace teristic, andtrain control'devices heldYat" I clear when both ofsaid stick relays are en-- 4.. In an automatic train control system, a" .trackand a conductor parallel thereto, dig

vided by insulated joints into blocks, a

ergized. 'I-

closedtrack circuit forv each 'blockincluding a relay, means controlled by the track'rc lays for connecting between the track and conductor of each block signalling currents having different,characteristics in the case of adjacent blocks. and the same char-acterisj tics in the case of alternate blocks,,a vehicle on the track having a translating device connectedv across the conductor and-track, two stick relays, selective mechanism controlled 1 by the translating device adapted to close the pickup circuit through one or'the'other relay upon reception of current'of one or the other characteristic, slow acting means for closing' the stick circuits Voftherelays upon reception of current ofeith'ercliarac- 1 teristlc, train control devices held at clear 2 When both of said stick relays are energized, I

and means for giving anindication when;

only one of said stick relays is energized;

5. In an automatic train control system,;a I

track and a conductor parallel} thereto clivided by insulated joints into blocks, a r closedtrack circuit including a relay; for

each block, a sourceot current connected through front contacts of the respective relays across the conductor and trackof blocks immediately in rear of the respective relays,

a circuit controller in'each of saidconn'ec-' tions, constant speed motors and means operatedthereby for closing, and] opening said controllers during regularlyre'curringf periods, the periods during which the 'con-- 1 trollers pertaining to alternate blocks are closed and open being respectively equal and substantially unequal to the periods in which the. controllers pertaining to the blocks adjacent thereto are closedand open,

a vehicle 'on the track having a relay con-. nected between the conductors and rails, a

constant speed motor on the-vehicle, switch mechanism operated by said vehicle motor and controlled by theuvehicle relay, train control devices governed by said switch mechanism, and means I controlled-by the switch mechanismqfor prevent ng-the 'clearance. I" thetra n control devices subsequent-.

ly to. the entry of the-vehicle into a block;

immediately in rear-of an occupied block until-the latter has been'cleared and the I block in advanceis clear.-

through front contacts of the respective track relays across the conductor and track of the blocks immediately in rear of the relays, a switch in each of said connections, constant speed motors and means operated thereby for closingand opening saidswitches during regularly recurring intervals, the periods in which the switches pertaining to al a the periods in which the vehicle relay is energized and deenergized are determined by the operation of the switches pertaining to one block or the adjacent block, slow acting means operated when the pick up circuit of either stick relay is closed adapted to hold the" relay energized for a predeterminedutime, and control devices held at clear so long as both relays are energized.

7. In an automatic train controlsystem for electric roads, a trackand a power conductor divided into blocks, means for connecting between the track and power conductor of each block a source of signalling current, when the block in ad'vance'is clear, means for afiecting the current differently in'the case of adjacent blocks, a vehicle having a translating device connected between the power conductor and rails, train control devices, and selective means controlled by said translating device for holding said tra'in control devices at clear upon reception of current from any blockand pre venting said mechanism from being cleared when once at danger indication until said translating device has been affected by current from twoadjacent blocks.

8. In an automatic train control system for electric roads, a track and a power con ductor divided into blocks, a vehicle on the track having a translating device connected between the power conductor and track, means for transmitting impulses through a the translating device at regularly recurring intervals under clear conditions, the duration of the impulses transmitted to the ve- 1 hicle in any one block being different than i that oi the impulses transmitted to the ve-' 'meansoperating upon reception of each impulse to hold closed stick circuits through the relays for a predetermined time, and

train control devices held at clear so long as both of said stick relays are energized;

9. In an automatic train control system forelectric roads,a track and a power conductor-divided into blocks, a vehicle on the track having a translating device connected between the power conductor and track,

means for transmitting impulses through to the adjacent block, train control devices,

a d selective mechanism controlled by' said translating device for preventing the clear' ance otsaid train control devices until said rents from two adjacent blocks.

10. In an automatic train control system tor electric roads, a track and a power contranslating device has been operated by curtrol devices, and selective mechanism con-: trolled by said translatingdevicefor clear-- 'ductor divided into'blocks, a vehicle on the ing said train control devices when the translating device has been operated currents irom two adjacent blocks.

llpin an automatic traincontrol system for. electric roads, a track and a power conductor divided into blocks, a vehicle on the track having a translating device connected between the power conductor, and track,

means for transmitting impulses through the under predetermined tra-fiic conditions, the

impulses being different in the case of adacent blocks, two stick relays; selective means controlled by the translating device for closing a pick-up circuit through one or the other relay according as impulses are received from" one block or the adjacent block, slow acting means controlled by the translating device for holding closedstick circuits forsaid rel ys for a predetermined ti anslating device at recurring intervals time, and train control devices held at'clear so' long as both stick relays are energizedl 12. In an automatic train control system ing electrical energy to the power conductor of diil erent characteristics in the case of different blocks, a vehicle travelingon the" track having mechanismselectively responsive to sa d currents, train control 'devices on the vehicle, and means'governedby said selective mechanism for clearing'saidftrain control devices when said mechanism has been successively operated by currents of a 7 case of different blocks, a vehicle on the track having a translating device connected across the conductor and track, train control devices governed by said translating device, and mechanism selectively responsive tosaid currents of different characteristics control devices until said mechanism has 9 14. In an automatic train control system,

a track and conductor parallel'thereto divided into sections, a vehicle on the track having translating devices energized from said conductor, means for energizing said conductor section with currents of different character in the case of adjacent sections,

train control devices governed by said translating device, and mechanism selectively responsive to said currents for preventing clearance of said train control devices until said mechanism has been successively actuated by currents of said different characters.

15. In an automatic train control system, a track and a conductor parallel thereto, divided by insulated joints into, blocks, a closed track circuit for each block including a relay, means controlled by the track relays for connecting between the track and conductor currents of different characteristics in the case of difierent blocks, a vehicle on the track having a translating device connected across the conductor and track,

mechanism on the vehicle selectively responsive to said currents, train control devices, governed by said translating device and means governed by the selective mechanism for preventing the clearance of said train control devices until said mechanism has been successively operatedby currents of a plurality of said characteristics.

16. In an automatic train control system,

I a track and a conductor parallel thereto, di-

vided by insulated joints into blocks, a

closed track circuit for each block including a relay, means controlled by the rack relays for connecting betweenv the track and conductor of each block signalling currents having different characteristics in the case 01"" adjacent blocks and the same characteristics in the caseof alternate blocks, a vehicle on the track having a translating de-' vice connected across the conductor and track, mechan sm on-the vehicle selectively responsive to said currents, train control devices governed by said translating device and means governed by the selective mechanism; for preventing the clearance of said train control devices until said mechanism has been successively operated by currents V y of different characteristics. for preventing the clearance of said train 17. In an automatic train control system, a track and a conductor parallel thereto, divided by insulated joints into blocks, a closed track circuit for each block including a relay, means controlled by the track relays for'connecting between the track and conductor ofeach block signalling currents having different characteristics in the case of adjacent blocks and the same character" istics in the case of alternate blocks, avehicle'on the track having a translating device connected fijCI'OSS the conductor and track, two stick relays, mechanism selectively responsiveito said currents adapted to close the pickup circuit through one or the other relay upon reception of current of one or the other, characteristic, slow acting means for closing the stick circuits of the relays upon reception of current of either characteristic, and train control devices governed by said translating device and held at clear when both of said stick relays are energized. V

18. In combination, a way-side conduc-' tor divided into sections, means for applying electrical energy having two distinctly different characteristics respectively to two successive sections of said conductor, a vehicle having a stick relay, means controlled by said current for closing a pick-up cir cuit through said relay upon reception of current of one character and a holding circuit through said relay upon reception of current of the other character and train governing means controlled by said relay; In testimony whereof I hereunto aflix my signature.

EDWARD to sAsN Tr. v 

